An international team of paleontologists has described a new ornithuromorph bird that lived during the Hauterivian stage of the Early Cretaceous epoch, approximately 131 million years ago.
The new bird belongs to Ornithuromorpha, a clade of birds that contains all extinct and extant species but not the Mesozoic Enantiornithes.
(...) The bird, named Archaeornithura meemannae, represents a new genus and species, and its discovery was reported May 5 in the journal Nature.
(...) Two partial skeletons of Archaeornithura meemannae were recovered from the Huajiying Formation in Sichakou basin, Fengning County, Hebei, northeastern China.
“The specimens preserve fairly advanced plumage including a well-developed alula (bastard wing) and fan-shaped rectrices. Both the alula and a fan-shaped tail are aerodynamically important for living birds during slow flight and increases manoeuvrability,” the paleontologists wrote in the paper.
“Bird fossils are extremely rare in the Mesozoic fossil record, and until the wealth of specimens discovered from Early Cretaceous deposits in northeastern China, very little was known about the early evolution of birds.”
“The Jehol Biota encapsulates a unique window into the biology and morphology of the oldest known avifauna.”
“Until now no ornithuromorphs had been described from the Huajiying Formation, which preserves very few fossil birds; because diversity is low and geographic area is restricted, the Huajiying Formation is interpreted as the earliest stage in the diversification of the Jehol Biota.”
“However, the discovery of a new species belonging to the specialized clade of waders – the Hongshanornithidae, indicates that ornithuromorphs themselves were already quite specialized at this point in their evolution.”
“This also strongly supports inferences that this clade originated in a semi-aquatic environment.”
The two specimens of Archaeornithura meemannae are housed in the Tianyu Natural History Museum of Shandong and are publicly accessible.
Aucun commentaire:
Enregistrer un commentaire